1. Field of the Invention
The present invention relates to a blood component measurement, and more particularly, to an apparatus and a method for measuring a blood component using the trans-reflectance of light irradiated to a transflective material disposed behind a test site.
2. Description of the Related Art
Diabetes is a modern lifestyle disease and currently has a prevalence of 5% of the global population, which is rising continuously. Diabetes is a chronic disease that has no perfect cure and requires lifetime self-management.
The term “self-management” indicates that a diabetic patient collects blood, performs the determination of a blood glucose level that is significantly affected by food intake, physical activity, drug or insulin therapy, and then provides the daily blood glucose determinations to a doctor to help the doctor choose a medical treatment.
However, due to pain and concern about infections by frequent blood collecting, a blood glucose test in itself increases the burden on diabetic patients. In this respect, methods of determining a glucose level in human blood by irradiating harmless light to a predetermined site of the human body and measuring the intensity of light that reacted with the human body, instead of blood-collecting, have been continuously studied.
Such studies have also been done on other blood components, in addition to blood glucose. A blood component measuring apparatus is generally classified into a reflection type and a transmission type. A reflection type blood component measuring apparatus measures a blood component in a human tissue by analyzing reflected light among incident light into the tissue. A transmission type blood component measuring apparatus measures a blood component in a human tissue by analyzing transmitted light among incident light into the tissue.
With respect to the reflection type blood component measuring apparatus, the mean path length of reflected light is very short, and thus, there arises a problem that the reflected light can hardly detect internal information of the human tissue. On the other hand, it is difficult to interface the transmission type blood component measuring apparatus with the human tissue or skin. Further, the optical power of transmitted light is too weak to measure.